Safety bindings for skis

ABSTRACT

A heel clip for releasably attaching a heel of a ski boot to a ski includes a framework pivotally mounted on the ski. A first member is pivotally connected to the framework for movement between first and second positions. In the first position, a second member pivotally connected to the first member engages a stop member and a clamp connected to the second member firmly engages the heel of a ski boot. When the heel exerts a sudden force sufficient to overcome a spring biasing the first member in the first position, the first member moves to the second position whereupon a groove in the second member receives therein the stop member thereby permitting the second member to pivot relative to the first member. This pivotal movement causes the clamp to release the heel of the ski boot.

United States Patent Laszlo [4 1 July 1 1, 1972 54] SAFETY BINDINGS FOR SKIS 3,490,783 1/1970 Shimizu ..280/1 1.35 T [72] lnventor: Nicolai Laszlo, Cluses, France Primary Examiner Benjamin Hersh [73] Assignee: Ets. Carpano 8: Pons, Cluses, France Assistant Examiner-Robert R. Song Filed: y 1970 Attorney-Robert E. Burns and Emmanuel J. Lobato Appl. No.: 56,960

[57] ABSTRACT A heel clip for releasably attaching a heel of a ski boot to a ski includes a framework pivotally mounted on the ski. A first member is pivotally connected to the framework for movement between first and second positions. In the first position, a second member pivotally connected to the first member engages a stop member and a clamp connected to the second member firmly engages the heel of a ski boot. When the heel exerts a sudden force sufficient to overcome a spring biasing the first member in the first position, the first member moves to the second position whereupon a groove in the second member receives therein the stop member thereby permitting the second member to pivot relative to the first member. This pivotal movement causes the clamp to release the heel of the ski boot.

10 Claims, 4 Drawing Figures PATENTEDJUL 1 1 1972 SHEET 1 BF 3 FIGA PATENTEUJHL 1 1 m2 SHEET 2 BF 3 PATENTEnJuL 1 1 m2 SHEET 3 OF 3 FIG. 5

1 SAFETY BINDINGS FOR SKIS BACKGROUND OF THE INVENTION The present invention relates to heel clips for skis which ensure the freeing of a boot attached by a heel clip to a ski when the heel clip is subjected to a force which exceeds a predetermined value irregardless of the direction of the force.

Numerous ski bindings are known in which the protection of the skier is assured by a double safety device, one at the toe, called the toe clip being a protection against a side force, the other on the heel called the heel clip," being a protection against the lifting force of the heel. These bindings are generally complicated and costly.

Also, ski bindings are known in which the component called the heel clip is generally provided with two springs and is designed to provide protection against lateral and lifting forces at the same time, but these bindings do not provide very good protection in the very frequent case where the force has simultaneous lateral and axial components. In fact, these bindings make the bones, muscles and tendons support the sum of the stresses due to the opposing lateral force to the opposing axial force. The result of these two forces is such that accidents occur before the binding has been released.

A remedy for this drawback has been sought by producing safety bindings comprising only one opposing spring acting on a ball co-operating with a mobile part comprising a groove in which the ball is located when the binding is in a closed position. However, such devices require a delicate adjustment and imply, for example, in the case of a vertical release, a movement of the holding component of the boot, the trajectory of which is substantially difierent to that of the boot, whereby large friction forces are developed between the holding component and the boot. Also, safety bindings are known which comprise an unlocking mechanism constituted by a lever with double articulation and ensuring the locking of the mechanism in the normal position by a knuckle joint effect. Other mechanisms ensure locking in the walking position by means of rollers which are displaced in relation to guiding ramps comprising bosses.

Such devices, locked in the closed position, require a sudden variation of an opposing force exerted by the mechanism just before the release and provide a blocking effect of the holding component in the locked position which detracts from the flexibility of function of the binding and the fineness of the adjustment of the releasing force. These mechanisms, which develop the irregular friction forces lack feasibility as their functioning characteristics depend on friction phenomena and vary with non-controllable parameters such as temperature and amount of wear on the surfaces in contact.

AIMS OF THE INVENTION An object of the present invention is to produce a heel clip which remedies the various aforementioned drawbacks, the mechanism of which heel clip is released in the case of excessive forces, but without locking effect, thus avoiding the surplus of energy necessary to breaking through the locking barrier, and functioning in a perfectly continuous manner up to the moment of release. In particular, the mechanism of the heel binding according to the invention is such that the ratio of the return force on the release force tends towards unity.

A further object of the present invention is to provide a heel clip which permits the opening of the clip to be carried out, when so wished, by a simple and quick movement and comprises means for regulating its longitudinal position.

According to the present invention, a heel clip for releasably attaching a heel of a ski boot to a ski comprises a framework rotatably mounted on the ski, a first member pivotally connected to the framework for movement between a first position and a second position, a second member pivotally connected to the first member for movement with the first member, a clamp connected to the second member and in the first position of the first member engaging with the heel of the ski boot for maintaining the ski boot in an operative position on the ski, a stop, the stop in the first position of the first member, engaging a portion of the second member to prevent pivotal movement of the second member relative to the first member, and in the second position of the first member entering a groove in the second member thereby permitting pivotal movement of the second member relative to the first member which pivotal movement releases the clamp from the heel, and resilient means biasing the first member in the direction of the first position the arrangement being such that the first member is moved from the first to the second position by a force applied by the heel, this force having a component of a predetermined value in a direction opposed to the force of the resilient means which causes the resilient means to compress.

Preferably, the stop is a roller freely mounted on a shaft, the shaft being supported by the framework.

The resilient means may be a spring, one end of the spring engaging a surface of a nut threadably engaged on. a screw supported by the framework.

Preferably, a second spring is provided, for biasing the second member against the stop.

DESCRIPT ION OF FIGURES An embodiment of the invention will now be described, by way of example, reference being made to the figures of the accompanying drawings in which:

FIG. 1 is a sectional view of the essential components of a heel clip according to the invention, in a walking position;

FIG. 2 is a sectional view of the essential components of the heel clip of FIG. 1, in a release position;

FIG. 3 is a perspective view of a pivot pin;

FIG. 4 is a sectional view of a regulating device for adjusting the longitudinal position of the heel clip; and

FIG. 5 is a plan view, partly in section, of the heel clip shown in FIG. 1.

DESCRIPTION OF A PREFERRED EMBODIMENT As shown, a heel clip for attaching a heel 1 of a ski boot to a ski 2 comprises a sole 4 attached to the ski 2 by means (not shown) and a framework including two spaced parallel flanges 21 (only one shown) interconnected by a rigid cover plate 37 supported on the sole 4. Three shafts 16, 22, 23 extend between the flanges 21. Shaft 16 pivotally supports one end of a member 13 and the member 13 has two side flanges interconnected by a web 14. The web 14 is formed with a hemispherical boss 15 about which is arranged one end of a coil spring 17. The opposite end of the spring 17 bears on a flange of a nut 18, which is threaded on a screw 19. The head of the screw 19 is mounted for free rotational movement in a through hole in the cover plate 37.

A shaft 12 extends between the side flanges of member 13 and a stirrup piece 10 is pivotally mounted on the shaft 12. The stirrup piece or member 10 is biased in a counterclockwise direction about shaft 12 by a spring 26. One surface of the stirrup piece 10 has a flat portion 25 which in the locked position of the clip (see FIG. 1), bears against a stop member comprising a polished roller 24 rotatably mounted on the shaft 23. Beneath the flat portion 25 is an arcuate groove of suffrcient size to receive the roller 24 (see FIG. 2).

The heel l is held against a sole plate 3 attached to the ski 2 by a clamp 9 attached to the stirrup piece 10 by a screw 11. The screw 11 is rotatably maintained on the stirrup piece 10 by rivetting its lower end and the upper end of the screw 11 freely passes through a hole in the stirrup piece 10.

The cover plate 37 covers the space between the flanges 21 and only the heads of screws l1, l9 protrude above the cover plate. The cover plate 37 thus protects the heel clip against possible damage.

When the heel clip is in the locked position (see FIG. 1), the heel 1 is releasably attached to the ski 2 under normal skiing conditions. Movement of the stirrup piece 10 and thus clamp 9 is opposed first by the flat portion 25 of stirrup piece 10 engaging the roller 24 and secondly by the force of spring 17 bearing against the web 14 of member 13.

The biasing force of spring 17 is such that it is overcome and compressed under the normal action of the lifting of the heel 1. During this compression, the stirrup piece is lifted up progressively in a direction substantially parallel to that of the movement of the heel 1. This is an advantage since it reduces to a minimum any friction between the heel l and the clamp 9.

When the force exerted by the heel 1 becomes excessive, that is, higher than a predetermined value of the opposing biasing force of spring 17, the stirrup piece 10 and member 13 together, both working as a single lever, pivot about shaft 16 in a counterclockwise direction and move away from the original position shown in FIG. 1, unit roller 24 is placed before the groove in the stirrup piece 10. Instantaneously, the stirrup piece 10 pivots in a counterclockwise direction about shaft 12 under the influence of spring 26, and occupies the position shown in FIG. 2. The clamp 9 moves with the stirrup piece 10 and the heel 1 is then released and is free to move away from ski 2.

The biasing force exerted by spring 17 can be adjusted by rotating screw 19 to move the nut 18. This enables the skier to determine the release force required to be exerted by the heel 1 before the heel is free to move away from the ski 2.

Similarly, the pressure exerted by clamp 9 on the heel 1 can be adjusted by turning screw 1 1.

It is important to stress that the device of the present invention functions without presenting any locking barrier and without bringing any sliding friction into play at the points of contact which are essentially sliding contact of the heel 1 with clamp 9 which has been reduced to a minimum, the rotation about shaft 12 and the rotation of member 13 about shaft 16.

ln order to ensure safety for a skier when lateral or oblique forces are applied to the heel clip, the framework is pivotally mounted on a pin 34 connected to a slide which is supported by the sole 4 (see FIG. 1). A ball race 35 is included in the pivoting arrangement to minimize friction. The pin 34, as shown in FIG. 3, has a flange at one end and has formed in one end surface thereof a radial groove 34b extending inwardly from the periphery of the flange. A ball 36 is supported in the radial groove 34b. The distance between the axis of pivotation of pin 34 and the center of the ball 36 is designated R. The upper side of ball 36 is received in the hemi-spherical boss 15.

Thus it is the coil spring 17 which ensures permanent contact between ball 36, pin 34 and boss 15. All lateral pulling, force or shock exceeding a predetermined value sufficiently compresses spring 17 and ensures the release of the heel clip by the same method as that made by the lifting of the heel 1, simultaneously with a rotation of the framework.

It should be emphasized that the total safety is thus ensured, according to the invention, by only one spring and only one adjustment, the ratio between the dangerous forces pulling in the lateral sense are able to be considered as a constant.

The heel clip also comprises means enabling the opening of the clip by a simple and easy manipulation.

A U-shaped level 38 is pivotally mounted at one end on a shaft 39 attached to the framework. Each of the spaced side arms of the lever 38 has a projection 40, stamped from the arm and positioned to engage shaft 12.

The side arms of lever 38 are situated on each side of flanges 21 of the framework and are riveted thereto and the side arms are pivotally mounted on the rivets 39. Projections 40 cooperate with the ends of the shaft 12 which project outside flanges 21 passing through two openings (not shown) in the flanges.

On the other end of lever 38 is attached a flexible strap for example, by riveting. Preferably, this strap 42 ends in a bucket 43 or clip attached to the skiers legs and thus serves as a safety strap preventing the ski 2 from escaping when the heel clip is released.

A pulling force exerted on the flexible strap 42 tends to pivot lever 38 in a clockwise direction about the shaft. 39. Projections 40 then exert an upward thrust on shaft 12, thereby causing the release of the heel 1 from the ski 2.

The heel clip further includes means for adjusting the longitudinal position of the heel clip in relation to a toe stop according to the length of the sole of the boot, the heel clip having a sprung pressure of the sole against the toe stop.

For this purpose a worm screw 45 provided with a manipulating head 46, accessible from outside the framework, freely turns in relation to the framework of the heel clip. The threads of screw 45 fit into grooves formed in a surface portion of sole 4 screwed onto the ski 2. Sole 4, screwed onto the ski, comprises longitudinal slides (not shown) into which the lower edges of flanges 21 of the framework engage. One part 47 is integral with the framework and forms a housing in which the worm screw 45 is provided. In another embodiment, the framework of the heel clip can be formed to constitute the housing. Further, a part 48 integral with screw 45 is pressed on the shoulder of manipulating head 46 and freely slides in relation to the framework. Two springs 49 and 50, placed on opposite sides of screw 45, press at one end against part 48 and at the other end against an external surface of the part 47. The springs are compressed before mounting, that is to say that whatever the position of screw 45, these springs are compressed.

When it is required to move the heel closer to the toe stop, the boot is lifted and the screw 45 is turned by means of the head 46. This rotation of movement causes a horizontal forward movement of a screw 45 and the pressure part 48.

This movement is transmitted by springs 49 and 50 to part 47, and the whole of the heel clip, guided by the slides in the sole 4, is moved towards the toe stop.

Movement in the reverse direction, that is, to move the heel clip backwards, is carried out by rotating screw 45 in the opposite direction. The horizontal movement of screw 45 is transmitted to part 47, thus to the framework, and screw 45 is in contact with the internal surface 52 of part 47.

What is claimed is:

l. A heel clip for releasably attaching a heel of a ski boot to a ski comprising: a framework rotatably mounted on the ski, a first member pivotally connected to the framework for pivotal movement between a first position and a second position, a second member having means therein defining a groove and pivotally connected to said first member for movement with said first member, a clamp connected to said second member having means for releasably engaging with the heel of the ski boot for maintaining the ski boot in an operative position on the ski when said first member is in said first position, a stop member engageable with a portion of said second member to prevent pivotal movement of said second member relative to the first member when said first member is in said first position and movable into said groove in said second member thereby permitting sufficient pivotal movement of the second member relative to the first member to release the clamp from the heel when said first member is moved into said second position, and resilient biasing means biasing said first member into said first position with a predetermined biasing force capable of being overcome by an external force applied by the heel of the ski boot having a force component greater in magnitude than said biasing force and acting in a direction opposite to said biasing force whereupon said first member is moved from said first position into said second position.

2. A heel clip according to claim 1, wherein said stop member comprises a shaft mounted on said framework, and a roller rotatably mounted on said shaft.

3. A heel clip according to claim 1, wherein said resilient biasing means comprises a screw threadably engaged on said framework, a nut adjustably threaded on said screw, and a spring engaging a surface portion of said nut.

4. A heel clip according to claim 1, including a spring for biasing said second member against said stop member when said first member is in said first position.

5. A heel clip according to claim 1, including a slide connected to the ski, a pin rigidly connected to the slide and having pivotally mounted thereon said framework, a flange on said pin having means therein defining a groove, and a ball disposed within said groove between said flange and a surface portion of said first member.

6. A heel clip according to claim 5, wherein said groove comprises a radial groove for engaging the ball.

7. A heel clip according to claim 1, including a lever pivotally connected to said framework, a projection projecting outwardly from said lever engageable with the pivotal connection between said first and second members in response to pivotal movement of said lever to permit said stop member to enter said groove in said second member thereby permitting pivotal movement of said second member relative to said first member to release said clamp from the heel of the ski boot.

8. A heel clip according to claim 7, including a strap connected to said lever.

9. A heel clip according to claim 1 including a sole rigidly connected to the ski, means defining a plurality of equi-spaced grooves in a surface portion of said sole, a worm screw having threads in meshing engagement with said grooves, and means connecting said worm screw to said framework for effecting movement of said framework along said sole in response to rotational movement of said worm screw.

10. A heel clip according to claim 9, including a manipulating head accessible from outside said framework and connected to said worm screw for effecting rotation of said worm screw. 

1. A heel clip for releasably attaching a heel of a ski boot to a ski comprising: a framework rotatably mounted on the ski, a first member pivotally connected to the framework for pivotal movement between a first position and a second position, a seconD member having means therein defining a groove and pivotally connected to said first member for movement with said first member, a clamp connected to said second member having means for releasably engaging with the heel of the ski boot for maintaining the ski boot in an operative position on the ski when said first member is in said first position, a stop member engageable with a portion of said second member to prevent pivotal movement of said second member relative to the first member when said first member is in said first position and movable into said groove in said second member thereby permitting sufficient pivotal movement of the second member relative to the first member to release the clamp from the heel when said first member is moved into said second position, and resilient biasing means biasing said first member into said first position with a predetermined biasing force capable of being overcome by an external force applied by the heel of the ski boot having a force component greater in magnitude than said biasing force and acting in a direction opposite to said biasing force whereupon said first member is moved from said first position into said second position.
 2. A heel clip according to claim 1, wherein said stop member comprises a shaft mounted on said framework, and a roller rotatably mounted on said shaft.
 3. A heel clip according to claim 1, wherein said resilient biasing means comprises a screw threadably engaged on said framework, a nut adjustably threaded on said screw, and a spring engaging a surface portion of said nut.
 4. A heel clip according to claim 1, including a spring for biasing said second member against said stop member when said first member is in said first position.
 5. A heel clip according to claim 1, including a slide connected to the ski, a pin rigidly connected to the slide and having pivotally mounted thereon said framework, a flange on said pin having means therein defining a groove, and a ball disposed within said groove between said flange and a surface portion of said first member.
 6. A heel clip according to claim 5, wherein said groove comprises a radial groove for engaging the ball.
 7. A heel clip according to claim 1, including a lever pivotally connected to said framework, a projection projecting outwardly from said lever engageable with the pivotal connection between said first and second members in response to pivotal movement of said lever to permit said stop member to enter said groove in said second member thereby permitting pivotal movement of said second member relative to said first member to release said clamp from the heel of the ski boot.
 8. A heel clip according to claim 7, including a strap connected to said lever.
 9. A heel clip according to claim 1 including a sole rigidly connected to the ski, means defining a plurality of equi-spaced grooves in a surface portion of said sole, a worm screw having threads in meshing engagement with said grooves, and means connecting said worm screw to said framework for effecting movement of said framework along said sole in response to rotational movement of said worm screw.
 10. A heel clip according to claim 9, including a manipulating head accessible from outside said framework and connected to said worm screw for effecting rotation of said worm screw. 